Conversion of hydrocarbon oils



i c. E. JAHNlG CONVERSION OF HYDROCARBON OILS Filed Nov. 2s, 1942 Sept. 10, 1946.

m .lAmN www. -j w. wm, hh N19 mm O WM :.v.. l. h'

@fo/M W Patented Sept. 10, 1946 CONVERSION OF I-IYDROCARBON OILS Charles E. Jahnig, Roselle, N. J.,` assignor to Standard Oil Development Company, a corporation of Delaware Application November` 28, 1942, Serial No. 467,170

13k Claims. 1

IIhis invenion relates to a process for the conversion of hydrocarbon oils and pertains more particularly to a process for converting hydrocarbon oils in the presence of a finely-divided conversion catalyst.

It has heretofore been proposed to crack hydrocarbon oils to form gasoline and other valuable products in the 'presence of a finelydivided cracking catalyst. In accordance with this general procedure, the oil to bey cracked `is passed through a cracking zone containing the catalystI in finely-divided state. The catalyst may be suspended in the oil and carried through the cracking Zone along With the oil, or the catalyst may be separately introduced and removed independently of the oil. y

During the cracking operation substantial quantities of combustible deposits are normally for-ined which impair the activity of the catalyst. As a result it has been the practice heretofore to withdraw the finely-divided catalytic material continuously from the cracking zone and to regenerate the material by burning the combustible deposits therefrom. During the burning of the combustible deposits, considerable heat is liberated which may be utilized in carrying out the cracking operation. In most cases, for example, the amount of heat liberated by burning of the combustible deposits formed during the cracking operation is sufficient to supply the heat requirements for the cracking process. In such cases the heat required for the cracking process is introduced into the oil by returning the hot, regenerated catalyst directly to the oil stream While at substantially the regeneration temperature and controlling the relative proportions of catalyst and oil circulating through the cracking and regenerating zone.

In some types of catalytic cracking operations the amount of combustible deposits formed during the cracking operation may be insufficient to supply the required heat for the operation. Furthermore, in other types of oil conversion processes, such as, for example, in the reforming of naphthapparticularly in an atmosphere of hydrogen, and in the dehydrogenation of hydrocarbons, the amount (3f-combustible deposits formed during the reaction is insucient to supply the heat requirements of the process. Consequently, it is necessary in such operations to add additional heat from some other source, such as by superheating of the oilfeed or supplying heat directly to the reaction zone either by external ringor by internal heating elements. O-ne particularly suitable method is toeupply fuel to the catalytic material in the regeneration zone. In other Words, instead of merely burning off the carbonaceous deposits during regeneration, additional fuel may be added during regeneration so as to supply the additional heat required.

However, there are certain disadvantages in the procedure last outlined, In the first place, the efficiency of the regeneration is reduced by the presence of ue` gases resulting from the added fuel. In the second place, the addition of fuel to the regeneration Zone requires that the catalyst passing through the regeneration zone be continuously subjected to an oxidizing atmosphere which may tend to oxidize` the catalyst and thus carry additional oxygen from the regeneration zone into the reaction zone where it would be again reduced at the expense of valuable oil feed. For example, when employing a chromium oxide containing catalyst, the chromium may become oxidized to a higher valence during regeneration and reduced by the feed or product gases to a lower valence during the reaction period.

The primary object of the present invention is to provide a process' in which the heat requirements for the operation are supplied by circulating hot, finely-divided catalytic material but.

which Will not be subject to the disadvantages v above mentioned.

A more specific object of the invention is to provide a process for the conversion of hydrocarbon oils, in which the heat is supplied by circulation of hot, finely-divided catalyst.

Clthe more specific objects Will be apparent from they more detailed descrip-tion hereinafter in which reference will be made to the accompanying drawing which is a diagrammatic illustration of one form of apparatus suitable for carrying the invention into effect.

Referring to the drawing, the reference character 0 designates a charge line through which the oil to be converted is charged into the system. For illustrative purposes, the process Will be described as applied tothe reforming of naphthas.v

The heavy naphtha to be reformed introduced through line l0 may be at room temperature or it may haveA been subjected to initial preheating and be either in liquid or vapor phase, or a mixture of both- In any event, the oil at the point of introduction is at a temperature materially below the desired reforming temperature. The oil passing through line I0 intermixes with a hot, finely-divided reforming catalyst discharging from column ll through control Valve l2. The amount of reforming catalyst added to the oil stream is suflicient to heat the oil to the reforming temperature and to supply the required heat for the reaction. The amount of catalyst introduced into the oil will depend upon the temperature of the catalyst, the temperature of the oil, and the reforming temperature desired.

When operating the reforming treatment at temperatures between 950 F. and l000 F. with a catalyst within the column Il at a temperature of 1100o F., the amount of catalyst introduced may range from 3 to 30 or more parts of catalyst per part of naphtha, depending upon the preheat temperature of the oil.

The catalyst employed may be any type of rcfcrming catalyst, such as a mixture of oxides of groups, III and VI of the periodic system. A particularly suitable catalyst may comprise, for example, a mixture of chromium oxides and alumina or molybdenum oxides and alumina. The mixture of oil and catalyst passes through transfer line i3 into a reactor lll. The suspension of oil and catalyst is preferably introduced into the bottom section of the reactor Hl below a perforated grid plate.

l5 and passes upwardly through the grid into the main body of the reactor. The reaction chamber below the grid plate i5 may be of reduced crosssection and the space below the grid may form a distributing zone for distributing the suspension uniformly over the cross-'section of the reaction chamber. The oil vapors passing upwardly through the reactor lli are preferably controlledL to permit the finely-divided catalytic material to settle into a relatively dense mass which is maintained in a highly turbulent, fluidized state by the upward passage of the oil vap-ors therethrough. To this end, the velocity of the oil vapors passing upwardly through the main section of the reactor i4 may range from 0.5 to 5.0 feet per second, depending upon the size and density of the catalyst particles.

The gaseous reaction products after passing through the dense, fluidized mass of catalytic material within the reactoi1 lil are removed overhead through line I6 and may be passed into a cyclone separator il or other suitable separating device for removal of entrained catalyst powder therefrom. The catalyst particles separated from the gasstream in the cyclone separator Il' are turned to the reactor lli through line i3.

The gaseous reaction products after passing through the cyclone separator i? may pass through a condenser i9 wherein the normally liquid constituents are condensed. The products from the condenser i9 may then pass to a receiver 2l in which the uncondensed gases separate from liquid condensate. Under operating pressures the uncondensed gases will contain a relatively high concentration of hydrogen together with lsome methane and ethane or other hydrocarbon gases. These gases are preferably recycled to the reaction zone through line 22 and compressor 23. If desired, extraneous hydrogen may be introduced into the system through line 24. Recycle gas is withdrawn, as desired, through line 20.

The reforming operation is preferably carried out under superatmospheric pressure, such as oi the order of from to Zoatmospheres, and the amount of hydrogen or recycle gases admixeol with` the oil may range from 3,000 to 10,000 cubic feet per barrel of oil treated. The temperature may range from 850 F. to 1100 F.

The condensate collected in the receiver 2l may be passed through line 25 to a stabilizer or fractionating towerZS in which the condensate is sul jected to distillation and fractionation to produce a product of the desired volatility. Light volatile hydrocarbons not required in the stabilized product may be removed overhead from the stabilizer 2S through line 2'! and may be subjected to further processing in suitable equipment (not shown).

The stabilized product may be removed from the bottom of the stabilizer through line 23. Suitable heating elements such as a heating coil 29 may be provided within the stabilizer 26 for supplying the required heat for distillation and fractionay tion of the product. While separator ll removes most of the nely-divided contact material, a small amount will be carried over into tower ZS and appear in the bottoms leaving through line 28. This material can be recovered by ltration, settling or other known means and returned to the system. It is often possible to carry out the operation so that the maj-or portion of the products leave from points above the bottom of the tower (e. g. 30) in which case the recovered material is concentrated into a relatively small amount of heavy bottoms and can be returned to the reactor as a slurry.

The reactor M is provided with a withdrawal conduit 3i for removal of catalytic material therefrom. The conduit 3i preferably has an extension projecting upwardly through the grid plate it into the main body of the reactor. A portion or all of the catalyst withdrawn from the reactor it through the Withdrawal conduit 3l may be passed through column 32 having a control valve into a stream of carrier gas introduced through line 34 and is carried thro-ugh line 35 into a heal,- ing chamber 36 which may be constructed similar to the reactor i4. The carrier gasl into which the catalytic material from the reactor ift discharges may be an inert gas such as spent combustion gases, steam or the like, or it may be an oxidizing gas such as air, or a fuel gas. The suspension of carrier gas and catalytic material lntroduced into the heater 36 passes upwardly through the perforated grid into the main body of the heater and the passage of the gases through the heater is controlled to maintain a dense, fluidized mass of catalytic material therein, as previously described in connection with the reactor I. The catalytic material contained in the heater S is heated to a temperature materially above the temperature in reactor l!! by the passage of the hot gases upwardly therethrough. To this end, a fuel gas lor liquid may be introduced through line 31. The heating gases may comprise hot carrier gas introduced through line 3d or spent regeneration gases from regenerator 38 hereinafter described, or additional fuel and air may be introduced into the` heater for heating the catalyst therein. It is preferred, however, to heat the catalyst within the heater 35 in a non-oxidizing atmosphere so as to prevent the oxidation of the catalytic material. The heating gas after passing through the heater 3E is removed overhead through line 39 to a cyclone separator 40 or other suitable separating device for removal of entrained catalytic material therefrom. The cata-- lyst separated from the heating gas in the cyclone separator il is returned to the heater 35 through line 4|. Line 4I preferably discharges into the heater 36vbelo'w the level of catalytic material contained therein.

The heating gas after passing th'rough the cyclone separator [i0 may be passed through line 42 to a heat exchanger or cooler 43 which may be in the form of a waste heat boiler or an oil preheater in which the temperature of the heating gases is materially reduced. The heating gas after passing through the cooler i3 may then pass through line 44 into a Cottrell precipitator 45 for further removal of catalytic material therefrom. The heating gas after passing through the Cottrell precipitator 45 may be rejected from the system through line l. When using contact materials which deteriorate with use, it is sometimes desirable to reject a portion of the material from the system. For this purpose, material may be removed through line 58.

The catalytic material after being subjected to the required heating in the heater 36 may be removed therefromV through conduit lll. A portion of the heated catalytic material withdrawn from theheater 35 through line 41 may ce passed into the column il and remixed with' the oil as hereinbefore described. The remaining portion of the catalytic material Withdrawn from heater 36 through line t? may be passed through a vertical column 48 and discharged through control valve 4553- into a stream of air entering through line 5i). The mixture oi air and catalyst formed in the line 5G may be then passed into the bottom of regenerator 38 below a perforated grid plate 5|. The catalytic material introduced into the regenerator 33 is subjected to oxidizing conditions to remove carbonaceous deposits formed thereon during the reforming operation. The suspension of regeneration gas and catalyst after passing through the regenerato-r 38 is transferred through line 52 into the bottom portion of the heater 3S below the perforated grid.

The velocity of the air passing upwardly through the regenerator 33 is preferably l.cony trolled to maintain a dense, turbulent mass of catalytic material undergoing regeneration therein. As illustrated, the catalytic material is removed from the regeneratcr 3e along with the spent regeneration gas passing overhead and isA again discharged into the heater 35.

The finely-divided material separated in the Cottrell precipitator et lmay be discharged through conduit 53 into a stream of air 54 and passed into the regeneration zone 33. The heat necessary for carrying out the reforming treatment is obtained by circulation of the catalytic material between the reactor M and the heater 3E, Which is separate and independent from the regenerator 3S. The amount of catalytic material circulating through the regenerator 38 may therefore be independently controlled to maintain the carbon content of the catalytic material at a predetermined point without the necessity of circulating all of the catalytic material through the regenerating zone wherein it is subjected to an oxidizing atmosphere.

. In order to circulate the catalytic material as hereinbeiore described, it is necessary t maintain the finely-divided material in a freely flowing, fluidized state. Furthermore, it is necessary to restore pressure on the catalytic material undergoing circulation to recycle or return it to the cracking and regenerating zone, as previously described. To this end, the conduits Il, 3| and ds'may be in the form of a standpipe in which a dense, iiuidized mass of catalytic material is maintained so as to develop a luistatic pressure at the bottom of said columns sufficient to overcome the pressure drop on the catalytic material undergoing circulation. In order to maintain the material within the columns Il, 3i and it in a freely flowing, fluidized state so as to develop iiuistatic pressure at the base thereof, a uidizing gas may be introduced into the columns at one or more spaced points as indicated.

In the drawing, the catalyst is removed from' the regenerator 38 along with the spent regeneration gas passing through line 52 and is introduced directly into the heater 3.5. If desired, however, the regenerator 33 may be constructed similar to the heater 3E and the reactor I4, and the regenerated catalytic material may be separately removed from the regenerator 33 through a separate bottom conduit, as illustrated in connection with heater 36 .and` reactor l.

In the above description, I have caused the material Withdrawn from reactor i4 to pass into the heating Zone and a portion of the heated. catalyst then passed to the regenerating Zone. In some cases, it is desirable to divide the catalyst removed from the reactor and pass a part to the heating Zone and the remainder directly to the regenerator. For example, if desired, a portion of the catalyst removed from the reactor I4 may be passed through column 55 and discharged through control valve 56 into the air line 5o from whence it passes directly into the regenerator 38 without rst passing through the heating Zone. In such. case, the column i3 may be omitted or blocked off 'so that all of the catalytic material from the heating zone 3% is returned to the reactor ii, or, if desired, a portion of the catalyst from the reactor may be combined with a portion of hot catalyst from the heater 36 and the resulting mixture passed to the regenerating zone.

Having described the preferred embodiment of the invention, it will be understood that it embraces such other variations and modifications as come within the spirit andl scope thereof.

What is desired to be protected by Letters Patent is:

l. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion Zone, contacting the oil in vapor form within said conversion Zone with a finely-divided contact material, maintaining said oil Within said conversion zone for a period sufficient to obtain a substantial convern sion thereof, continuously removing contact material from said conversion Zone, passing at least a portion of the Contact material so withdrawn through a heating Zone, heating said contact material within said heating zone by direct contact with a heating gas to a temperature materially above the temperature maintained within said conversion zone, mixing a portion of the hot contact material from said heating Zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion Zone, passing the mixture so obtained back to said conversion Zone, controlling the amount of contact material circulating through said heating and conversion Zones to maintain said conversion zone at the desired con- Version temperature, regenerating a portion of Y the contact material Withdrawn from said conversion zone and thereafter returning the same to said conversion zone.

2. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion zone, contacting the y heating said contact material Within said heating zone by direct contact with a heating gas to a temperature materially above the temperature Within said conversion zone, mixing a portion of the hot contact material from said heating Zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion zone, continuously passing the mixture so obtained back to said conversion zone, passing another portion of said contact material from said heating zone through a regenerating zone, maintaining an oxidizing atmosphere within said regenerating zone to remove carbonaceous deposits contained thereon, and combining regenerated catalyst with the remainder of said catalyst prior to passing the same to said conversion Zone.

3. A pro-cess for the conversion of hydrocarbon oils `which comprises passing the oil to be converted through a conversion Zone, contacting the oil within the conversion Zone with a finely-divided Contact material, maintaining said oil in contact With said contact material within said conversion Zone for a period sufficient to obtain a substantial conversion thereof, continuously removing Contact material from said conversion zone, passing a portion of the contact material so withdrawn through a heating zone, heating said contact material Within said heating Zone by direct contact with a heating gas to a temperature materially above the temperature maintained Within said conversion Zone, mixing a portion of the hot contact material from said heating zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion Zone, thereafter passing the mixture so obtained to said conversion zone, passing the remainder of said contact material withdrawn from said conversion zone through a regenerating Zone, burning combustible deposits contained on said contact material during passage through said regenerating zone, and combining the regenerated contact material with the remainder of the contact material from said heating zone prior to passing the same to the conversion Zone.

4. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion Zone, contacting the oil Within said conversion Zone with a finely-divided conversion catalyst, maintaining said oil within said conversion zone for a period sufficient to obtain a substantial conversion thereof, continuously removing finely-divided contact material containing combustible deposits from said conversion Zone, passing the contact material so withdrawn through a heating zone, maintaining said finely-divided material during passing through said heating Zone in a non-oxidizing atmosphere, heating said contact material within said heating zone to a temperature materially above the temperature maintained in said conversion Zone, thereafter passing a portion of the heated conversion catalyst from said heating zone to said conversion zone, controlling the amount of conversion catalyst circulating 'through said heating and conversion Zones `to maintain said conversion zone at the desired conversion temperature, passing another portion of the conversion catalyst from said heating zone directly to a regenerating zone, maintaining said conversion catalyst within said regenerating zone in an oxidizing atmosphere to burn combustible deposits therefrom, and thereafter passing said regenerated catalyst to said heating zone,

5. A process for the reforming of hydrocarbon oils which comprises passing a naphtha fraction through a reforming zone, contacting said naphtha within said reforming zone with a finelydivided reforming catalyst, maintaining said naphtha in contact With said ,catalyst for a period sufficient to obtain substantial reforming thereof, continuously removing finely-divided reforming catalyst from said reforming zone, passing at least a portion of said reforming catalyst through a heating zone, maintaining said reforming catalyst during passage through said heating zone in a non-oxidizing atmosphere, heating said reforming catalyst Within said heating zone by direct contact with a heating gas to a temperature materially above the temperature maintained in said reforming Zone, mixing at least a portion of the hot reforming catalyst from said heating zone with the naphtha to be converted having a temperature materially below the temperature maintained Within said reforming zone, thereafter passing the mixture so 0btained to said reforming zone, controlling the amount of reforming catalyst circulating through said heating and reforming zones to maintain said reforming zone at the desired reforming temperature, passing a portion of the reforming catalyst withdrawn from said conversion zone through a regenerating zone, subjecting said catalyst during passage through said regenerating zone to an oxidizing atmosphere to remove carbonaceous deposits formed thereon during the reforming process, and thereafter returning the regenerated catalyst to the reforming Zone.

6. A process for the conversion of hydrocarbon oils which comprises passing the oil in vapor form upwardly through a conversion chamber, contacting the vapors during passage through said conversion chamber with a finelydivided contact material, controlling the velocity of the vapors passing upwardly through said conversion chamber to maintain said finely-divided contact material in a relatively dense, luidized, turbulent state, maintaining said oil vapors in contact with said contact material for a period sufficient to obtain a substantial conversion thereof, thereafter separating conversion products from the finely-divided contact material, continuously removing said contact material from the conversion chamber, passing at least a portion of the conversion catalyst so removed through a heating zone, heating said contact material during passage through said heating zone by direct contact with a heating gas to a temperature materially above the temperature maintained in said conversion chamber, mixing a portion of the hot contact material from said heating zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion chamber, thereafter passing the mixture so obtained to said conversion chamber, controlling the amount of contact material circulating through said heating zone and said conversion chamber to maintain said conversion chamber at the desired conversion temperature, regenerating a portion of the contact material removed from said conversion chamber, and thereafter returning the regenerated contact material to the conversion chamber.

7. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion Zone, contacting the oil during passage through said conversion Zone -with a finely-divided contact material, maintaining the oii in contact with said contact material for a period suiiicient to obtain a substantial conversion thereof, continuously removing contact material from said conversion zone, passing at least a portion of the contact material so removed through a heating zone, passing a heating gas upwardly through said heating zone in direct contact with said finely-divided contact material, controlling the velocity of the heating gas passing upwardly through said heating zone to maintain said contact material in a dense, turbulent condition, heating said contact material within said heating zone by contact with said heating gas to a temperature materially above the temperature within said conversion zone, mixing at least a portion of the hot contact material from said heating zone with the oil to be converted having temperature materially below the temperature maintained within said conversion zone, thereafter returning the mixture so obtained to said conversion zone, controlling the amount of Contact material circulating through said conversion Zone and said heating zone to maintain said conversion Zone at the desired temperature, regenerating a portion of the contact material removed from said conversion zone in a regenerating zone separate and independent from said heating zone, and thereafter returning the regenerated contact material to the conversion Zone.

8. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion zone, contacting the oil within said conversion zone with a finely-divided conversion catalyst, maintaining the oil in contact with said conversion catalyst for a period sufficient to obtain a substantial conversion thereof, continuously removing conversion catalyst from said conversion zone, passing at least a portion of the contact material so removed through a heating zone, heating said conversion catalyst during passage through said heating Zone by direct contact with a heating gas tor a temperature materially above the temperature maintained in said conversion Zone, mixing a portion of the hot conversion catalyst from said heating zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion zone, thereafter returning the mixture so obtained to said conversion zone, controlling the amount of conversion catalyst circulating through said heating and conversion zones to maintain said conversion zone at the desired conversion temperature, passing a portion of the conversion catalyst removed from said conversion Zone to a regenerating zone, passing an oxidizing gas upwardly through said regenerating Zone in direct contact with said finely-divided conversion catalyst, controlling the velocity of the oxidizing gas passing upwardly through said regenerating zone to maintain a relatively dense, fluidized, turbulent mass of conversion catalyst within said regenerating Zone, and returning regenerated conm version catalyst to the conversion zone.

9. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted upwardly through a conversion Zone containing a body of iinely-divided conversion catalyst, controlling the velocity of the oil vapors passing upwardly through said conversion zone to maintain said finely-divided conversion catamaintaining said oil vapors in contact with said conversion catalyst within said conversion zone for a period suicient to obtain a substantial conversion thereof, continuously removing conversion catalyst from said conversion zone, passing at least a portion of the conversion catalyst removed from said conversion zone to a heating Zone, passing a non-oxidizing and heating gas upwardly through said heating acne in direct contact with the finely-divided conversion catalyst contained therein, controlling the velocity of the heating gas passing upwardly through the heating zone to maintain said conversion'catalyst in a dense, turbulent, fluidized condition therein, heating the conversion catalyst within said heating zone by contact with said heating gas to a temperature materially above the temperature within said conversion Zone, mixing at least a portion of the hot conversion catalyst from said heating zone with the oil to beconverted having a temperature materially below the temperature maintained within said conversion zone, thereafter returning the mixture so obtained to said conversion Zone, controlling the amount of conversion catalyst circulating through said heating Zone and conversion zone to maintain said conversion Zone at the desired conversion temperature, regenerating a portion of the conversion catalyst removed from said conversion zone in a regenerating Zone separate and independent from said heating zone and returning the regenerated conversion catalyst to the conversion zone. f

10. A process for the conversion of hydrocarbon oils lwhich comprises passing the oil to be converted in vapor form upwardly through a conversion zone containing a body of finely-divided conversion catalyst, controlling the velocity of the oil vapors passing upwardly through said conversion zone to maintain said conversion catalyst in arelatively dense, turbulent condition, maintaining said oil vapors in contact with said conversion catalyst for a period sufcient to obtain substantial conversion thereof, continuously removing thel conversion catalyst from the conversion zone, passing at least a portion of the conversion catalyst removed from sai-d conversion zone through a heating Zone, heating said catalyst during passage through said heating zone by direct contact with a heating gas to a temperature materially above the temperature in said conversion zone, mixing a portion of the hot conversion catalyst from said heating Zone with the oil to be converted having a tempera ture materially below the temperature maintained within said conversion zone, thereafter returning the mixture so obtained to the conversion zone, controlling the amount of conversion catalyst circulating through said heating Zone and said conversion Zone to maintain said conversion zone at the desired temperature, passing a portion of the catalyst removed from said conversion Zone to a regenerating zone separate and independent from said heating zone, passing an oxidizing gas upwardly through said regenerating zone in direct contact with said conversion catalyst contained therein, controlling the velocity of the oxidizing gas passing upwardly through said regenerating zone to maintain a dense, turbulent mass of conversion catalyst within said regenerating zone, and thereafter passing regenerated conversion catalyst from said regenerating zone to the conversion zone.

11. A process for the conversion of hydrocarbon oils which comprises passing the oil to be converted through a conversion Zone containing a mass of finely-divided conversion catalyst, maintaining the oil in contact with said conversion catalyst within the conversion Zone for a period sufficient to obtain a substantial conversion thereof, continuously removing conversion catalyst from said conversion Zone, passing at least a portion of the conversion catalyst so removed through a heating zone, passing a heating gas upwardly through said heating Zone in direct contact with the conversion catalyst contained therein, controlling the velocity of the heating gas passing upwardly through the heating zone to maintain a dense, turbulent mass of conversion catalyst within said heating zone, heating said conversion catalyst within the heating zone by contact with said heating gas to a temperature materially above the temperature within said conversion zone, mixing at least a portion of the hot conversion catalyst from said heating zone with the oil to be converted having a temperature materially below the temperature maintained within said conversion zone, thereafter returning the mixture so obtained to the conversion zone, passing a portion of the conversion catalyst removed from` said conversion Zone to a regenerating zone, passing an oxidizing gas upwardly through said regenerating zone in direct contact with the conversion catalyst contained therein, regulating the velocity of the regenerating gas passing upwardly through said regenerating zone to maintain a dense, turbulent mass of conversion catalyst therein, and returning regenerated conversion catalyst from said regenerating Zone to said conversion zone.

12. A process for cracking hydrocarbon oils which comprises passing the oil to be cracked through a cracking zone in direct contact with finely-divided cracking catalyst contained therein, maintaining the oil in contact with said cracking catalyst within said cracking Zone for a period suicient to obtain a substantial cracking thereof, continuously removing finely-divided cracking catalyst containing carbonaceous deposits from said cracking zone, passing at least a portion of the cracking catalyst removed from said cracking zone to a heating zone, heating the cracking catalyst during passage through said heating zone by direct contact with a heating gas to a temperature materially above the temperature maintained in said cracking zone, mixing a portion of the hot cracking catalyst from said heating zone with the oil to be converted having a temperature materially below the temperature maintained within said cracking zone, thereafter returning the mixture so obtained to said cracking zone, controlling the amount of cracking catalyst circulating through said cracking and heating zones to maintain said cracking zone at the desired cracking temperature, passing a portion of the catalyst removed from the cracking zone through a regenerating zone separate and independent from said heating Zone, subjecting said catalyst within said regenerating Zone to an oxidizing atmosphere to burn carbonaceous deposits contained thereon and thereafter returning the regenerated catalyst to the cracking Zone.

13. A process for reforming hydrocarbon oils which comprises passing a naphtha fraction through a reforming zone, contacting said naphtha within said reforming Zone with a finely-divided reforming catalyst, maintaining said naphtha in contact with said catalyst within said reforming zone for a period sufcient to obtain a substantial reforming thereof, continuously removing finely-divided reforming catalyst from said reforming zone, passing reforming catalyst so removed through a substantially non-oxidizing heating zone, heating said reforming catalyst duringpassage through said heating zone ex- "a clusively by direct contact with an inert heating gas to a tempe-rature materially above the temperature maintained in the reforming zone, mixing a portion of the hot reforming catalyst from 

